A failed attempt at Tom Corbett’s legislative agenda, a long and likely hot summer under way, a single question now dominates many Harrisburg political conversations: When will Tom Corbett quit? When will he announce he is not running for a second term, setting the stage for a GOP gubernatorial primary next May to select his successor?

Why Corbett should quit looms painfully obvious, even to many who support him.

Only about one-third of Pennsylvania voters give him a positive job performance — abysmal for an incumbent less than 15 months from Election Day. Roughly one in four voters thinks he deserves another term. Worse perhaps is that his much-vaunted legislative “agenda,” including liquor privatization and pension reform, has gone nowhere, badly damaging his image for effectiveness.

To many, Corbett looks like a one-term governor — so politically damaged that he probably can’t be saved. This ominous sentiment isn’t limited to Pennsylvania.

A horde of respected, independent national pundits and publications has already weighed in, concluding he is so unpopular he can’t be re-elected. One has named Pennsylvania as the most likely state in the nation to change parties in 2014. Another, the prestigious National Journal, is already speculating in print about his possible Republican successors.

Corbett could find numerous and compelling reasons to quit.

Yet, it’s not going to happen. Corbett is not going to quit, not going to withdraw as a candidate for re-election and, in fact, not even face a major opponent for renomination by the Republican Party. Despite all the arguments to the contrary, he will run for re-election in 2014 and will be the nominee of his party.

Why he won’t quit boils down to a half-dozen hard realities about state politics, the Republican Party and Tom Corbett himself. Together, they reveal much about state politics and perhaps more about the current state of GOP politics.

• Hope Springs Eternal — It’s not clear who the Democratic nominee will be or what strengths and weaknesses the person will bring to the ticket. In past non-open seat elections both parties have fielded exceptionally weak candidates. The 2014 Democratic field looks strong at this point, but it is too early to tell. Undoubtedly, the tone of the Democratic primary as well as the eventual nominee could provide Corbett with an opening he badly needs.

• The Skunk Factor — Certainly, there might be Republicans who would run against Corbett in a party primary. But few want to be the skunk at the picnic. Though weak, Corbett would probably defeat all comers, but he would emerge from a primary even weaker than now — almost surely losing the fall contest. So the payoff is likely defeat in the primary and ultimate blame for the loss in November. A winning strategy this is not.

• No Viable Replacement — Corbett may be weak but he is still an incumbent with all the advantages incumbents have running for re-election. Some national publications have reported internal maneuvering among Republicans to replace Corbett. That’s not going to happen. The most obvious replacements, Congressmen Jim Gerlach, Pat Meehan and Charles Dent, would have to give up super-safe seats to run. Moreover, the large structural debt facing the next governor intensified by the fractious Harrisburg infighting among Republicans makes doubtful any of them would take on the challenge.

• Show of Weakness — A Corbett withdrawal would be a tacit admission that the last four years of a Republican administration had been an abysmal failure. Inevitably, Corbett’s GOP successor as gubernatorial candidate would be saddled with defending Corbett’s legacy in November without any of the advantages of incumbency. It would be a field day for the Democratic nominee.

• Not the Real Problem — The Corbett administration has failed to secure its major policies, but the lion’s share of the blame falls to Republicans in the Legislature. There, personal and policy differences have eviscerated Corbett’s agenda. It’s hard to imagine any Republican gubernatorial replacement that can bridge the big ideological differences that exist, or mend the personal differences.

• It’s Always about the Money — All statewide campaigns run on big money. Republicans usually have it; Democrats usually need it. In 2014, Corbett still retains the support of deep-pocketed conservatives as well as the business community. He will be reasonably well financed with more than sufficient resources to wage an energetic campaign. Money alone won’t win this one for Corbett. But a lack of money won’t lose it for him either.